The Earth's atmosphere and gravity present several issues for spacecraft launched from, or landing on, Earth. For example, it is necessary to achieve a high velocity to escape Earth's gravitational pull. Objects traveling at high velocities in Earth's atmosphere experience significant resistance and friction. As a result, special geometries and heat shielding is required. This also true of spacecraft reentering Earth's atmosphere. If the heat shielding or the geometries are not precise, then the spacecraft could experience a catastrophic failure. However, not all extraterrestrial masses share characteristics of Earth's atmosphere.
Extraterrestrial masses such as a moon, asteroid, or small planet, often have little if any atmosphere and far less gravity that Earth. These variations afford a unique opportunity to develop a class of spacecraft that have less mass and are not bound by the strict geometry of spacecraft launched from Earth. Moreover, the new type of spacecraft can be custom tailored to the needs of habitable bases located on these masses.
What is needed is a transit craft that can act as a transport landing vehicle for astronauts to and from the surface of an extraterrestrial mass.